The widespread deployment of advanced sensors in the buildings sector has the potential to unleash significant energy savings, yet this is currently limited by the high cost of hardware and installation. Wireless communication can greatly reduce installation cost. However, wireless sensors currently rely on batteries with limited lifetime, or indoor-light harvesting, with high device cost and reduced power availability. Directed RF energy harvesting can provide robust power using simple, inexpensive components. Plug-and-play sensors that self-locate can reduce installation and commissioning labor costs while providing dense environmental and room configuration information.